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961.
M. P. D'Alessandro H. P. W. Kozakewich K. R. Cooke G. A. Taylor 《Pediatric radiology》1996,26(1):19-21
The appearance of pulmonary nodules in a child with a solid malignancy undergoing chemotherapy is a clinically worrisome event. The diagnosis in such cases is not always metastatic disease, and the differential diagnosis should include granulomatous disease, atelectasis, pneumonia, inflammatory pseudotumor, hamartoma, radiation pneumonitis, and bronchiolitis obliterans with organizing pneumonia. There is no consistent radiologic feature to help distinguish benign from malignant causes of these new lesions. However, repeat chest CT 4–6 weeks after the lesions are first noted can be used to track lesion progression and may obviate the need for biopsy. 相似文献
962.
M O Lobb S J Duthie R W Cooke 《European journal of obstetrics, gynecology, and reproductive biology》1986,22(1-2):17-21
The neonatal survival and incidence of periventricular haemorrhage (PVH) in very-low-birthweight (VLBW) infants who present by the vertex are not influenced by the use of episiotomy. This study does not support the routine use of episiotomy for pre-term vertex deliveries. 相似文献
963.
P Hutchings L O'Reilly N M Parish H Waldmann A Cooke 《European journal of immunology》1992,22(7):1913-1918
The use of immunosuppressive drugs in the management of autoimmunity penalizes a large part of the immune system for the misdemeanors of a small minority of T cells. An ideal form of therapy would be one in which it were possible to render the immune system tolerant of the inciting antigens with minimal effects on other responses. We here show that it is possible to re-establish self tolerance in an animal model of insulin-dependent diabetes mellitus without prior deletion of CD4+ T cells using a short course of therapy with a non-lytic monoclonal antibody to the CD4 adhesion receptor on T cells. This tolerance can be achieved even when diabetogenic cells are already in the pancreas. Primary responses to antigens given after therapy has ceased are normal and secondary responses to antigens seen prior to, but not during, the period of antibody therapy can remain unaffected. This suggests that intervention with selected CD4 antibodies may have significant advantages over and above that provided not only by conventional immunosuppression but also over that provided by a depleting antibody. 相似文献
964.
AIMS: To assess the efficacy of serum prostate specific antigen (PSA) in the diagnosis of prostatic cancer. To compare this tumour marker with serum acid phosphatase (ACP) in order to define the more effective diagnostic test. METHODS: Serum samples from 349 patients attending a urology department were assayed for PSA and ACP. Histological assessment of prostatic biopsy samples was used as the standard by which the diagnostic effectiveness of the tumour markers was determined. RESULTS: Mean serum PSA results from patients with prostatic carcinoma (159 (SEM 35) ng/mL) were significantly different to those from patients with benign prostatic hyperplasia (4.0 (0.53) ng/mL). As there was considerable overlap of results, test sensitivities and specificities were calculated for various decision points. The sensitivity and specificity of PSA at a level of 10 ng/mL were 61.2% and 93.0% respectively, while for ACP at a level of 0.8 U/L they were 47.6% and 89.9%. The areas beneath receiver-operator curves (0.81 for PSA and 0.72 for ACP) indicated that PSA gives better diagnostic information than ACP. For a stated incidence of cancer, posttest probabilities following a given PSA result have been calculated. CONCLUSIONS: PSA is a more effective serum marker for prostatic carcinoma than ACP. We present a table so that for similar patient groups posttest probabilities for prostatic cancer can be assessed for a given serum PSA level. 相似文献
965.
Screening for cytomegalovirus antibody in a donor insemination program: difficulties in implementing The American Fertility Society guidelines 总被引:1,自引:0,他引:1
With the recommendations of The American Fertility Society that all donors and recipients in a donor insemination programme should be screened for CMV antibody, we have documented the prevalence of CMV antibody in donors, recipients, and their partners in our clinic. Forty percent of our donors were CMV-positive, and in only 35% of the couples were both partners negative. The implications of using exclusively CMV-negative donors are examined. The necessity for further research on the detection and the transmission of various strains of CMV and the effects of cryopreservation on them is emphasized. 相似文献
966.
Prolonged increase in digital blood flow following iloprost infusion in patients with systemic sclerosis 总被引:1,自引:0,他引:1
M Rademaker R H Thomas G Provost J A Beacham E D Cooke J D Kirby 《Postgraduate medical journal》1987,63(742):617-620
Thirteen patients with Raynaud's phenomenon secondary to systemic sclerosis received three 8-hour infusions of a synthetic prostacyclin analogue (Iloprost) on consecutive days and were followed-up over a period of 10 weeks during the winter of 1985/86. Six weeks after infusion, digital peripheral vascular resistance had fallen (P less than 0.05) and dicrotic notch proportion of pulse amplitude increased (P less than 0.05). Digital blood flow and pulse amplitude (measured by photoplethymography) were also increased but did not reach statistical significance. The trend of improvement in these blood flow parameters was still evident after 10 weeks. The number of cutaneous lesions (digital ulcers, etc) fell from 26 lesions before infusion to only 7 lesions by the end of the study, confirming the subjective improvement reported by the patients. 相似文献
967.
A prospective study of multiple needle biopsies versus a single open biopsy for testicular sperm extraction in men with non-obstructive azoospermia 总被引:13,自引:9,他引:4
Little is known about the efficacy and the factors affecting the outcome of
fine needle aspiration biopsy of the testis for sperm retrieval in
azoospermic men with defective spermatogenesis. A prospective study was
designed to compare the efficacy of needle and open (window) testicular
biopsies for testicular epididymal sperm extraction (TESE) in 35
consecutive men with azoospermia due to defective spermatogenesis
undergoing testicular biopsy for intracytoplasmic injection of oocytes.
Each of the consecutive 35 patients underwent TESE using a 19 gauge
butterfly needle followed by a window (1-1.5 cm-sized incision) testicular
biopsy in the same procedure. The extraction of spermatozoa into culture
medium was compared with the assessment of testicular biopsies by
histology, the mode of biopsy (needle or open biopsy) and the amount of
tissue retrieved by either method. Testicular spermatozoa were retrieved in
22 (63%) who had an open testicular biopsy compared with five (14%)
patients who had multiple needle biopsies, respectively; the difference was
statistically significant. Open testicular biopsy retrieves more testicular
tissue than needle biopsy. Needle testicular biopsy retrieved testicular
spermatozoa in 50% of those with hypospermatogenesis, 10% with focal
spermatogenesis and in no patients with maturation arrest or Sertoli
cell-only pattern. In contrast, sperm retrieval was successful in 100%, 90%
and 66% of those with respective histologies using open testicular biopsy.
Other than bruising, for which they required no analgesia, none of the
patients suffered any obvious complications associated with traditional
testicular biopsy. We conclude that open testicular biopsy is more
effective than needle biopsy for the retrieval of testicular spermatozoa in
azoospermic men with defective spermatogenesis. The difference observed may
be related to the amount of testicular tissue retrieved and to the
influence of testicular histology.
相似文献
968.
Immune complexes were detected by plain and immunoelectron microscopy amongst electron-dense material that rapidly formed and extended over and into the cartilaginous surfaces of immune arthritic rabbits' knees. The sinuous extension of electron-dense material into the surface matrix was associated with fragmentation and detachment, resulting in erosions. The findings implicate the formation of immune complexes in the destructive process of the matrix. Since the eroded pannus-free matrix of rheumatoid cartilage surfaces contains extensive concentrations of immune complexes, the data of this immune arthritis model suggest a causative relation between immune complexes and matrix loss in rheumatoid arthritis. 相似文献
969.
C. M. Fraser A. Fisher M. J. Cooke I. D. Thompson T. W. Stone 《Psychopharmacology》1997,130(4):334-342
The Y-maze was used to assess spontaneous alternation behaviour in mice to examine possible interactions between the N-methyl-D-aspartate receptor channel blocker dizocilpine and purine receptor agonists and antagonists. Scopolamine reduced spontaneous
alternation. Dizocilpine also produced a dose-dependent reduction in alternation scores, which was accompanied by an increase
in locomotion. The selective A1 adenosine receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (CPX) had no effect when administered alone, or in combination
with scopolamine. However, when co-administered with dizocilpine, CPX reversed both the deficit in alternation behaviour and
also the increase in locomotion induced by dizocilpine. The A1 selective agonist N
6-cyclopentyladenosine (CPA) had no effect on either locomotion or alternation scores when administered alone, but in combination
with scopolamine, CPA attenuated the scopolamine-induced deficit. CPA had no significant effect on the dizocilpine-induced
deficit. The A2 selective agonist N
6-[2-(3, 5-dimethoxyphenyl)-2(2-methylphenyl)-ethyl]adenosine (DPMA), had no effect on spontaneous alternation when administered
alone, but did cause a depression of locomotion. DPMA had no significant effect when co-administered with scopolamine, but
reversed the deficit in spontaneous alternation, and the increase in locomotion induced by dizocilpine. The A2 selective antagonist 3,7-dimethyl-1-propargylxanthine (DMPX) had no effect when given alone or in combination with scopolamine,
but when co-administered with dizocilpine, DMPX reversed the reduction in spontaneous alternation caused by dizocilpine. It
is concluded that dizocilpine has a detrimental effect on spontaneous alternation which is mediated partly by A1 and A2 adenosine receptors.
Received: 21 March 1996 / Final version: 6 November 1996 相似文献
970.
M E Gore J C Cooke E Wiltshaw J M Crow D O Cosgrove C A Parsons 《British journal of cancer》1989,60(5):751-754
We have carried out a prospective study on the impact of computed tomography (CT) and ultrasonography (US) on the management of patients with carcinoma of the ovary. Seventy-eight CT and 88 US scans were performed on 94 patients. Clinicians decided patient management prospectively at the time the CT and/or US was ordered. Clinical assessment differed from the result obtained by CT or US in 45% of cases (35/78 and 40/88, respectively). CT and US altered patient management in only a minority of cases (14/78, 18% and 9/88, 10% respectively). Even when the scan and clinical assessments differed, management was only altered on 14/35 (40%) occasions after CT and on 9/40 (23%) occasions after US, a difference which was not significant. In patients with clinically undetectable disease, management was altered by CT on 17% of occasions and by US on 10%. We conclude that in patients with carcinoma of the ovary CT and US alters patient management in a minority of cases. In view of current financial restrictions in health care, clinicians should be more selective in the use of these imaging techniques. Furthermore, we recommend that similar prospective studies are performed for other clinical situations. 相似文献